Broad band dielectric relaxation spectra are reported for some poly(ether imide)s based on 2,2-bis[4'-(3 '',4 ''-dicarboxyphenoxy) phenyl] hexafluoropropane dianhydride and 1,2-bis(4-aminophenyl) diamines derived from ethylene glycol oligomers of different specific lengths. Spectra were obtained over the temperature range -150--20 degrees C and which covers the low temperature relaxation region for these materials. In the case of the polymer with no EO units, a single broad dipole relaxation feature is observed. The introduction of a single -CH2CH2O- unit significantly broadens the relaxation suggesting the existence of two separate relaxation processes. Increasing the number of EO units per repeat to 3 and 6, allows resolution of two relaxations processes; one due to an oscillatory-librational motion of the imide segment and the other to conformational changes involving the EO sequences. Analysis of the relaxation using the Havriliak-Negami equation indicates that both processes deviate for the description of a simple dipole relaxation and indicate cooperativity of bond motion in the relaxation process. The ability of a polymer to change its packing density is reflected in changes in the relaxation spectra on annealing and changes in the value of the higher frequency limiting values of the permittivity. The activation energy for dipole reorientation ranges from a value of 34 kJ mol(-1) for the relaxation of the dipole associated with the imide relaxation process to a value of 60 kJ mol 21 for the polymer containing 3 EO segments. In this latter polymer, system a lower activation energy process is observed with a magnitude of similar to 15 kJ mol(-1) associated with conformational changes of the aliphatic ether. (C) 2014 Wiley Periodicals, Inc.